Nucleolus organizer region
A REGION OF A CHROMOSOME WHERE NUCLEOLI FORM DURING INTERPHASE, AND WHERE GENES ENCODING THE LARGEST RRNA PRECURSOR TRANSCRIPT ARE TANDEMLY ARRAYED.
Nucleolar organizer; Nucleolar organizer region; Nucleolar Organizing Regions; Nucleolar Organizing Region; Nucleolar Organization Region; Nucleolar organization region; Nucleolar organizer regions; Nucleolar organizing regions; Nucleolar organizing region
Nucleolus organizer regions (NORs) are chromosomal regions crucial for the formation of the nucleolus. In humans, the NORs are located on the short arms of the acrocentric chromosomes 13, 14, 15, 21 and 22, the genes RNR1, RNR2, RNR3, RNR4, and RNR5 respectively.